A rivet disclosed in Patent Document 1 is known as a rivet operable from one direction. The rivet of Patent Document 1 includes a sleeve having a flange and a core member, which is inserted into the sleeve. A mounting hole is arranged in a laminated layer sheet, in which a plurality of sheets is laminated. After the sleeve is inserted into the mounting hole from one direction, the core member is inserted into the sleeve from the same direction in the similar manner. In this way, the sheets are fixed to one another.
In particular, in the rivet of Patent Document 1, an opening is formed in the tubular body of the sleeve. A plurality of pivoting pieces is coupled to the edge of the opening via thin hinges. When the core member is inserted into the sleeve, each pivoting piece is pushed by the core member so that the pivoting piece pivots outward. As a result, the laminated layer sheet is sandwiched by the flange and the pivoting pieces in the outwardly pivoted state, and is integrally fixed.
In the rivet of Patent Document 1, a plurality of projections is formed on the outer circumferential surface of the core member, and a plurality of recesses is formed on the inner circumferential surface of the sleeve. When the core member is inserted into the sleeve, each projection of the core member engages with the corresponding recess of the sleeve. This restricts the core member from escaping from the sleeve. Such escape of the core member is restricted so that the core member remains in the sleeve. This restricts the pivoting pieces from pivoting inward.